Hydrography is the science of mapping or charting the seafloor’s features. Hydrographers measure water depth, and search for shoals, rocks, wrecks, and other features on the seafloor that could be hazards to navigation. Cartographers use the hydrographic data to create and update nautical charts. Increasingly, that data is also used in a wide range of ocean and coastal applications.

Coast Survey directs field programs for hydrographic surveys; develops survey specifications; tests new technology; and improves procedures to increase efficiency in survey data acquisition, data processing, and chart production.